NATS 1880 Lecture Notes - Lecture 3: Star System, Cosmic Microwave Background, Hubble Space Telescope

• School: York University
• Department: Natural Science
• Course: NATS 1880
• Professor: Michael De Robertis

Document Summary

The universe is very old - meaning there has been a lot of time and real estate for life to develop and evolve. The elements of life are widespread: carbon and long chain organic molecules (raw material) have been detected in the galaxy. No reason to think that the process that evolved on earth could not happen elsewhere. Way) -> our galaxy in local group -> local group in local super-cluster -> all part of universe. The orion nebula (m42) is ~1500 ly away the milky way: 100 000 ly across and home 200 billion stars. The universe contains all the matter and energy in existence. Matter such as planets, stars, etc (or baryonic matter) is 4% Dark matter has a gravitational influence is 28% Dark energy (vacuum energy) is a repulsive force is 68% Stars are created in galaxies by the collapse of clouds of hydrogen and helium. Stars release energy as a result of nuclear fusion.